A portable electronic device (e.g., a cellular telephone) may be provided with one or more motion-sensing components (e.g., accelerometers, gyroscopes, etc.) that may be utilized for determining a movement state of the electronic device (e.g., whether the device is being carried by a user that is walking, running, or cycling). Often, however, the data provided by such motion-sensing components is insufficient on its own to enable a reliable determination of a device movement state.